Badri (Manoj Joshi) heads a Brahmin family whose ancestral palace is believed to be haunted by the ghost of Manjulika, a Bengali classical dancer. Siddharth (Shiney Ahuja) and Avni (Vidya Balan), the son and daughter-in-law of Badri's elder brother, return to their native village from America and decide to stay in their ancestral palace. Here, Siddharth is crowned as the king, his right to the throne.Events take a twist when Avni opens a forbidden locked room that contains the ghost of Manjulika. Unnatural events start taking place inside the palace. Avni falls in love with the place and learns about Manjulika and her tragic story. Badri and Batuk Shankar (Paresh Rawal) try to ward off the evil eye with the help of a priest, Shri Yagyaprakashji Bharti (Vikram Gokhale), but unfortunately the priest has gone to London and is unsure when he might return.Siddharth starts suspecting Radha (Amisha Patel) for all the strange occurrences. He thinks she has gone crazy since he was supposed to marry her, but married Avni instead. He calls his friend/psychiatrist Dr. Aditya Shrivastav (Akshay Kumar) to try to figure out what the problem is with Radha. Once Aditya reaches the palace, things become comical, as everyone thinks he is a fool, though he is in fact very intelligent. Aditya eventually realizes that Radha is not at fault, and that someone else behind it all. One night, he encounters Manjulika and dares her to strike. The ghost angrily vows to take her revenge on the auspicious day of Durgashtami.During the engagement of Nandini, Siddharth's cousin, and Sharad Pradhan (Vineeth), Avni spills food on Sharad and takes him away to get him cleaned. When Aditya and Siddharth search for her, they see that there is a struggle between Avni and Sharad, and quickly intervene. Siddharth thinks that Sharad was violating Avni, but Aditya tells him that Avni is actually the real culprit.